Is this a new installation with zero running time? There are about 3 different lengths of pushrods for stovebolt engines, and I believe the hydraulic lifter engines have a different length pushrod than the ones for mechanical lifters. It might be a very good idea to pull that side cover so the whole valve train is exposed. Did you pre-fill the lifters or are you trying to make the adjustments without oil in the lifter barrels? The oil makes a big difference in the "feel" the pushrod has during an adjustment sequence.
Jerry

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